viral hemorrhagic fevers - walter reed army … · viral hemorrhagic fevers. ... – media –...

UNCLASSIFIED

WRAIR- GEIS 'Operational Clinical Infectious Disease' Course

Viral Hemorrhagic Fevers

Disclaimer

The views expressed in this presentation are those of the speaker and authors, and do not reflect the official policy of the Department of Army, Department of

Defense, or U.S. Government

- COL Arthur Lyons - COL Mark Kortepeter

Acknowledgements

Outline • VHFs – General Summary of What is Known…

– Overview of syndrome – Geographic distribution – Animal hosts and vectors – Nosocomial and occupational risks – Estimated incubation periods

• Selected Pathogens (time permitting):

– Ebola – Crimean-Congo Hemorrhagic Fever – Lassa Fever – Hantaviruses

• Emerging Threats (time permitting)

OUTBREAK (1995) 3 weeks on top of US box office Grossed: $190M ($50M budget)

Will Cover Some Steps to Avoid….

Source: mirror.co.uk

The “Slammer”

Source: vox.com

1995 Kikwit Zaire ZEBOV Outbreak Source: Don Noah

Definition • Viral hemorrhagic fever (VHF):

• Fever • Malaise • Myalgia • Prostration • Bleeding diathesis • Severe multi-organ failure • Enveloped, single-stranded, RNA viruses

•Hemorrhagic fever virus (HFV) is a term used to generically identify those agents that cause VHF

Overview of Etiologic Agents of VHFs

Flaviviridae Flavivirus Omsk HF Kyasanur forest disease (including Alkhurma) Dengue

Yellow fever

Family Genus Species Filoviridae Ebolavirus Zaire, Sudan, Ivory Coast, Bundibugyo, Reston

Marburgvirus Lake Victoria marburgvirus

Arenaviridae Arenavirus Lassa, Lujo (“Old World”) Junin, Machupo, Guanarito, Sabia, (“New World”)

Bunyaviridae Nairovirus Crimean-Congo hemorrhagic fever

Phlebovirus Rift Valley fever Hantavirus Hantaan, Seoul, Puumala, Dobrava, Sin Nombre

Family Features • Small RNA viruses, enveloped in a fatty (lipid)

coating, acid sensitive. • Survival is dependent on an animal or insect

host, called the natural reservoir; geographically restricted to the areas where their host species live. Humans are not natural reservoirs.

• All aerosol-infectious – Exception: dengue viruses

Family Features • Humans are infected when they come into contact with

infected hosts. However, with some viruses, after the accidental transmission from the host, humans can transmit the virus to one another.

• Human cases or outbreaks of HF occur sporadically and irregularly. The occurrence of outbreaks cannot be easily predicted.

• With a few noteworthy exceptions, there is no cure or established drug treatment for VHFs.

Disease (Virus) Distribution Host/Vector Other risks Incubation CFR

Ebola Africa, Philippines (ER)

Bats/Pigs? Nosocomial 2-21 25 - 88% (~67%)

Marburg Africa Bats? Nosocomial 5-10 82%

Lassa (and Lujo) Africa (Western) Rodent Nococomial 5-16 15-80%

Junin Argentina Rodent Nococomial 7-14 10-30%

Machupo Bolivia Rodent Nococomial 9-15 5-30%

Guanarito Venezuela Rodent Nococomial 7-14 23%

Sabia Brazil Rodent Nococomial 7-14 1 of 3

Crimean-Congo Europe, Asia, Africa

Tick, herding animals, birds?

Nosocomial, slaughterhouse

3-12 3 - 70% (~20-30%)

Rift Valley Fever Africa Mosquito slaughterhouse 2-5 1 - 50%

Hantaviruses Worldwide Rodent Nosocomial (Andes virus)

9-35 1-15% (~50% HPS)

Omsk Soviet Union Tick 2-9 0.3-5%

Kyasanur India Tick 2-9 3-5%

Alkhumra Middle East Tick (Camels?) Butchers 2-9 ~30%

Yellow Fever Africa, Americas Mosquito 3-6 20-50%

Military Relevance: Weaponization

• Bioterrorism (BT) – Hoaxes to mass casualties – Small attacks may be incredibly disruptive

• 2001 Anthrax: ADLs, Commerce, Government, $$

• VHFs are important considerations in Bioterrorism (BT) preparedness

– Reputation from popular literature, cinema – Media – Dramatic clinical syndrome(s) produced

• Stability and infectivity of VHF viruses is sufficient (or could be enhanced) to produce effective WMD

The “Deadly” VHFs

VIRUS Ebola Zaire

Marburg

Lassa

Lujo

CCHF Rift Valley fever

Mortality Rate 75-90%

25-90%

15-20% of hospitalized

80%

3-70% (typically 20-30%) 50% of patients with hemorrhagic form

Overview of VHFs

Geography of VHF

Source: Mike Bray, NIAID

Alkhurma

Lujo

Distribution of CCHF Distribution of RVF

CDC © 2013 WHO © 2008

Distribution

• Virus and disease(s) are limited to where the host species live(s)

– Geographically restricted: Rodent (New World arenaviruses) – Geographically diverse: Rodent (Hantavirus); common rat

(Seoul virus) • Occasionally, exported hosts can spread disease

– Marburg (Germany, Yugoslavia) • Human travelers

– Ebola

Why do we even care? Most of these infections are nowhere near the United States. Why should

the U.S. use resources and risk personnel?

Overview of VHFs

I E " I T.

e

- - - -

Weekly December 18, 2009 / 58(49) ;1377-1381

Imported Case of Marburg Hemorrhagic Fever --- Colorado, 2008 Marburg hemorrhagic fever (MHF) is a rare, viral hemorrhagic fever (VHF); the causative agent is an RNA virus in the family F iloviridae, and growing evidence demonstrates that fruit bats are the natural reservoir of Marburg virus (MARV) (1, 2) . On January 9, 2008, an infectiou s disease physician notified the Colorado Department of Public Health and Environment (CDPHE) of a case of unexpla ined febrile illness requiring hospitalization in a woman who had returned from travel in Uganda. Testing of early convalescent serum demonstrated no evidence of infection with agents that cause tropical febrile illnesses, including VHF. Six months later, in July 2008, the patient requested repeat testing after she learned of the death from MHF of a Dutch tourist who had visited the same bat-roosting cave as the patient, the Python Cave in Queen Elizabeth National Park, Uganda (3) . The convalescent serologic testing revealed evidence of prior infection with MARV, and MARV RNA was detected in the archived early convalescent serum. A public health investigation did not identify illness consistent with secondary MHF transmission among her contacts, and no serologic evidence of infection was detected among the six tested of her eight tour companions. The patient might have acquired MARV infection through exposure to bat secretions or excretions while visiting the Python Cave. Travelers should be aware of the risk for acquiring MHF in caves or mines inhabited by bats in endemic areas in sub-Saharan Africa. Health-care providers should consider VHF among travelers returning from endemic areas who experience unexplained febrile illness.

- - - -

Approximately 22 miles Downtown DC

Ebola Reston

How are VHFs Spread?

1 - Inhaling or ingesting excretions/secretions from rodent hosts (urine, feces, saliva)

2 - Bite of an infected arthropod (tick, mosquito) or crushing

infected arthropod

3 - Nosocomial/lab transmission – contact with human or animal blood/body fluids/tissue

4 - Artificially generated aerosols (biowarfare)

5- Exposure to infected animals (Care, consumption, slaughter)

Overview of VHFs

Sources: independent.co.uk Stroke-survivors.org Mklop.com

Crimean Cong He ic TransmFisesveior n cycle of CCHF

Overview of VHFs

How are VHFs spread? Airborne? - In monkeys, possible airborne transmission between cages 3 m - Lung tissue, along with nares, pharynx, and conjunctiva w/virus - Monkeys and guinea pigs able to be infected via airborne route

Arch Pathol Lab Med 1996;120: 140-5. Int J Exp Path 1995;76:227-36.

Lancet 1995;346:1669-71. Arch Virol 1996(suppl);11:115-134.

Overview of VHFs How are VHFs spread? Human to Human? Only dengue and yellow fever virus have adapted to efficient

“human-to-human” transmission (via mosquitoes). Typical story for nosocomial transmission:

- Patient Zero enters the health care facility - VHF is not recognized or infection control not followed - Unrecognized spread from blood/body fluid contact - Health care personnel among the victims - Victims carry infection to the community - Close family members and those doing burial rites infected

No proven human to human respiratory transmission

- A possibility in rare circumstances, in later stages of disease

Source: MMWR 1995;44(25):475-79.

Number of infected health care workers declined after barrier nursing practices were begun during the Ebola HF outbreak in Kikwit, DRC, 1995.

Critical Care Clinics (2005) 21:765-783.

Overview of VHFs How are VHFs spread? Nosocomial Filoviruses – Ebola and Marburg Arenaviruses – Lassa, Junin/Machupo (rare) Bunyaviruses – CCHF, Andes virus (a cause of HPS) Flaviviruses – Dengue (rare – from blood splash)

Lassa – most common imported VHF (if dengue not included)

Transmission of VHFs rarely if ever occur prior to

onset of symptoms

Pathogenesis • Varying degrees of, singly or in combination:

– Direct viral damage – Disseminated intravascular coagulation (DIC) – Hepatic damage – Vascular damage – Cytokine release

• Fatal cases – Lymphoid depletion (ex: hantavirus: immunopathology)

Overview of VHFs • Clinical Presentation: Nonspecific, Wide Variety

– Prodrome (3-4 days) • Fever, Headache, Malaise, Arthralgias, Myalgias, fatigue • Nausea, Abdominal pain, Non-bloody diarrhea

– Early signs • High Fever, Tachycardia, Tachypnea, Conjunctivitis, Pharyngitis • Flushing, Skin Rash • Prostration, capillary leak (nondependent edema, effusions)

– Late • ↓ BP, Hemorrhagic diathesis, Petechiae, Mucous membrane • Conj. hemorrhage, Hematuria, Hematemesis, Melena

– Severe Manifestations • DIC, Circulatory Shock, CNS dysfunction, Death • Mortality rates can be as high as 90%+

Symptoms/Signs • Hemorrhage

– Most cases: South American hemorrhagic fevers – <50%: Lassa – Requires thrombocytopenia and capillary damage

• Shock, florid hemorrhage, extensive CNS damage – Poor prognosis

• Physical signs early in the course may be suggestive – Low BP – Postural hypotension – Petechial hemorrhage – Conjunctival injection common (ex: HPS)

Clinical Features of VHFs

Adapted from: Peters CJ

Disease Clinical Therapeutic Synopsis

South American HF Hemorrhage, dysarthria, tremor usual

Ribavirin, vaccine (limited availability)

Lassa fever Prostration/shock/deafness: hemorrhage less so

Ribavirin

Rift Valley Fever HF low; rapid course: DIC/hepatitis/retinal vasculitis/encephalitis

?Ribavirin Vaccine (limited availability)

Crimean Congo Hemorrhagic Fever

HF, hemorrhage, DIC Ribavirin No vaccine

Hemorrhagic Fever with Renal Syndrome (HFRS)

Febrile prodrome, shock, renal failure, hemoconcentration

Supportive care, dialysis ?ribavirin Vax: China, Korea

Hantavirus Pulmonary Syndrome (HPS)

Similar to HFRS, but pulmonary edema vice renal failure

ICU management Ribavirin not useful

Clinical Features of VHFs

Adapted from: Peters CJ

Disease Clinical Features Therapeutic Synopsis

Marburg/Ebola Weight loss/prostration, rash, hepatitis, uveitis, orchitis, arthralgias common in convalescence

Supportive Vaccine in advanced clinical development

Yellow Fever Severe HF with jaundice Vaccine Dengue Need sequential infection

with heterotypic serotypes

Supportive care Vaccines in clinical development

Tick-Borne Flavivirus Biphasic: fever, thrombocytopenia, hemorrhage, followed by neurologic signs

No specific therapy or vaccine

Courtesy of Drs. Zaki & Peters

Overview of VHFs

Overview of VHFs

• Lab Abnormalities – Leukopenia

• Esp. South American HF • Lassa with low, normal or increased WBC • Hantavirus: leukemoid counts

– Anemia – Hemoconcentration

• Extreme: hantavirus – Thrombocytopenia – Elevated liver enzymes – May have renal dysfunction – Coagulation abnormalities

• Modestly abnormal

Overview of VHFs • Lab Abnormalities

– Coagulation abnormalities • No patterns diagnostic • Prolonged bleeding time • Prothrombin time • Activated PTT • ↑ fibrin degradation (i.e. increased D-dimer) • ↓ fibrinogen • DIC: CCHF, filovirus, severe RVF, early HFRS

– AST, amylase – Urinalysis: reflects circulatory status

• Proteinuria: reflecting capillary leak? • Hematuria • Oliguria • Azotemia

Overview of VHFs

• Lab Abnormalities and Disease Presentations – These are not hard and fast rules.

– There will be overlap with many of these infections

– Nonspecific initial presentations

• Mimic many common syndromes • Must have SA • Ask the question!

Overview of VHFs

• Differential Diagnosis • Malaria • Typhoid fever (Salmonella) • Rocky Mountain Spotted Fever

(Rickettsia rickettsii) • Other rickettsioses • Leptospirosis • Meningococci • Q fever (Coxiella burnetti) • Plague • Influenza

• Viral meningitis / encephalitis – Henipaviruses

• HIV / co-infection • Hemorrhagic smallpox • Vasculitis (i.e. autoimmune diseases) • Thrombotic thrombocytopenic purpura

(TTP) • Hemolytic-uremic syndrome (HUS) • Hemophagocytic syndrome • Shigella

Clinical presentation: Fever, hemorrhage/purpura, thrombocytopenia, CNS signs, elevated LFTs, leukopenia, thrombocytopenia, DIC, multisystem / multi-organ failure

- - - -

- - - -

Conjunctival injection & subconjunctival hemorrhage Source: Current Science/Current Medicine (Peters CJ, Zaki SR, Rollin PE). Viral hemorrhagic fevers. In: Fekety R, vol ed. Atlas of Infectious Diseases, p10.1-10.26, Volume VIII, 1997.

Bolivian Hemorrhagic Fever (Machupo virus – New World Arenavirus)

- - - -

- - - -

Left arm. Ecchymosis, diffuse, severe. (1 week after clinical onset)

Source: Robert Swaneopoel, PhD, DTVM, MRCVS, National Institute of Virology, Sandringham, South Africa.

Crimean-Congo Hemorrhagic Fever (CCHF)


Source: healthierpakistan.com

CCHF


Source: glogster.com


Source: data.fao.org

BOLIVIAN HEMORRHAGIC FEVER (MACHUPO)

Source: histopathology-india.net

KOREAN HEMORRHAGIC FEVER (HANTAAN)

Source: emedecine.medscape.com

Argentine Hemorrhagic Fever

Source: telemedicine.org

Dengue Hemorrhagic Fever

Source: magnustoday.net

Maculopapular rash Photo credit: Martini GA, Knauff HG, Schmidt HA, et. al. Ger Med Mon. 1968:13:457-470.

Marburg Infection Human

Hemorrhagic Fever with Renal Syndrome (HFRS)

Source: lookfordiagnosis.com

Overview of VHFs • Diagnosis

– High index of suspicion (know what is in your AO) – Lab findings

• Thrombocytopenia , low WBC, anemia, transaminitis, increased bilirubin, prolonged PT, PTT, increased D-dimer, decreased fibrinogen

• Acute phase: detection of RNA by RT-PCR, finding viral proteins by ELISA, or viral isolation (BSL-4)

• As patients improve, markers of acute infection disappear and IgM appears

– Hantaviruses: antibodies present in serum at time of onset of disease (IgM capture ELISA)

Lab Diagnosis • Virus isolation (Gold Standard, but requires BSL-4 Lab) • Electron microscopy • Reverse transcription - polymerase chain reaction (RT-PCR) • Rapid ELISA techniques (most easily employed) • Immunohistochemistry (IHC) & in situ hybridization (ISH) of

infected tissues

Overview of VHFs • Treatment

– Rapid atraumatic hospitalization – ICU admission if available – Early Supportive Care (the foundation of treatment)

• Careful management of fluid and electrolytes • Blood transfusions as needed (whole blood if available) • Hemodialysis as needed • Vasopressors and cardiotonic drugs (some do not respond to fluids)

– Monitor for signs of hypotension and shock

• Cautious sedation and analgesia • Watch for secondary infections (add broad spectrum antibiotics, malaria RDTs vs. empiric treatment)

– Treatment of Disseminated Intravascular Coagulation (DIC) • Coagulation studies and clinical judgment as guide • Replacement of coagulation factors / cofactors • Platelet transfusions • No aspirin, NSAIDs, anticoagulant therapies, or IM injections

– Use acetaminophen for pain or fevers

Overview of VHFs • Treatment

– Ribavirin • Investigational drug, compassionate use • Contraindicated in pregnancy • All Arenaviridae (Lassa, Junin, Sabia, Lujo) • Consider for Bunyaviridae (Hantaan, CCHF) – not RVF • NO UTILITY FOR FILOVIRUSES OR FLAVIVIRUSES

– Monoclonal antibodies (experimental)

– Immune (convalescent) plasma • Arenaviridae (Junin, Machupo; ?Lassa) • Passive immunoprophylaxis post-exposure? • Experimental studies in animals have not proven efficacy against

filovirus infection • NOT READILY AVAILABLE

Overview of VHFs

• Ribavirin Treatment – 30 mg/kg IV single loading dose – 15 mg/kg IV q 6 hr for 4 days – 7.5 mg/kg IV q 8hr for 6 days

• Ribavirin Post-Exposure Prophylaxis – 500 mg PO q 6 hr for 7 days – 35 mg/kg x 1, then 15 mg/kg Q8hrs x10 days (WHO)

Note: Parenteral (Rx) and oral Ribavirin (PEP) are investigational and available only

through human use protocols (ahem….contact USAMRIID or LRMC through ID consult)

Borio L, et al. JAMA 287(18):2391-2405, 2002 McCormick JB et. al. N Eng J Med 314(1):20-26, 1986 Jahrling PB et al. J Infect Dis 141:580-589, 1980

Risks: - Upset stomach - Reversible hemolytic

anemia - Arrhythmias - Teratogenic

JAMA 2002;287:2391

Overview of VHFs

RIBAVIRIN TREATMENT

Contained Casualty Mass Casualty Adults Same as previous slide Load 2g po x 1, followed by 1.2g po qd

divided in 2 doses (if >75kg pt), or 1g po qd in 2 doses (if pt <75kg) for 10 days

Pregnant Same as adults Same as adults Children Same as Adults, dosed

according to weight Loading dose 30mg/kg po x1, followed by 15mg/kg qd in 2 divided doses for 10 days

Prevention / Control

• Junin Candid 1 – ARGENTINE HF – Live, attenuated – Safe and efficacious – Protects monkeys against Bolivian HF – NOT AVAILABLE IN THE UNITED STATES

• YELLOW FEVER – Licensed 17D vaccine, highly efficacious – Live virus vaccine – Reports of vaccine associated deaths – Cannot be used in persons with egg allergy

Prevention / Control: None Licensed in the U.S.

• Rift Valley Fever – Formalin-inactivated

• safe but requires 3 shots, intermittent booster • limited supply

– Live, attenuated MP-12 • Phase II testing

• Ebola – Adenovirus (Ad3) vectored +/- DNA prime – Vesicular Stomatitis Virus (VSV) vectored – VEE replicons – Virus-like particles (VLP)

• Marburg

– Recent NHP study at USAMRIID: 100% survival following challenge w/ lethal dose of MBGV and then post-exposure treatment w/ recombinant VSV-GP Marburg vaccine

Experimental Products in the Pipeline • Recombinant human monoclonal antibodies

– MB-003, ZMAb, ZMapp • Vaccines mostly in pre-clinical stage (few human studies)

– DNA vaccines – Live viral vector vaccines – Virus-like particles vaccines

• Drugs: – Pyrazinecarboxamide derivative, T-705 (favipiravir) – Broad-spectrum nucleoside analogue (BCX4430) – Recombinant nematode anticoagulant protein (NAP) – AVI-6002 (antisense oligomers) – Clomiphene/Toremiphene – Retanizone (Vit A derivative)

Source: sites.psu.edu

Experimental Products • Why don’t we just test these products on the sick?

• The story of TGN1412… – CD28-monoclonal antibody – Intended for treatment of B-cell CLL and rheumatoid arthritis – Tested in animals previously and noted to be safe – Clinical Trial (2006)

» First in humans study » Given at a fraction of the dose found safe in animals » All 6 human volunteers were hospitalized that same day

» Multi-organ failure » Cytokine storm » Prolonged hospitalization

Bottom line: We don’t know if they are safe

vVSV-ZEBOV • Attenuated, replication-competent, recombinant VSV-based

vaccine expressing the glycoprotein of a Zaire strain of ZEBOV

• Two Phase 1 trials (26 x 2 participants) – WRAIR and NIH

• Placebo-controlled, double-blind, dose escalating studies – 20 million PFU vs. 3 million PFU

• Adverse events – Injection site pain, myalgias, fatigue

• Seroconversion (Day 28): 100% – GMT 4079 (20 million) vs 1300 (3 million); P<0.001

• VSV viremia detected for short duration Source: Regules JA, Beigel JH, Paolino KM et al, A Recombinant Vesicular Stomatitis Virus Ebola Vaccine — Preliminary Report, New. Engl. J. Med., DOI: 10.1056/NEJMoa1414216

Overview of VHFs

• Prevention – BACK TO THE INITIAL CASE PRESENTATION…

• 18 HCPs identified as being HIGH risk exposures

• Offered oral ribavirin post-exposure prophylaxis

• 2 individuals had more significant symptoms to meds

Both were found to have developed

antibodies to the CCHF virus

Overview of VHFs • CDC Recommendations - when to go “hot”

– Standard Precautions in initial assessments – Private room upon initial hospitalization

• “Barrier precautions” – including face shields, surgical masks, eye protection within 3 feet of patient (double glove, impermeable gown)

– Have your VHF “battle buddy” double check you

• Negative pressure room not required initially, but should be considered early to prevent later need for transfer

– Airborne precautions if prominent cough, vomiting, diarrhea,

hemorrhage • E.g. HEPA masks, negative pressure isolation

MMWR 1988;37(S-3):1-16. MMWR 1995;44(25):475-79.

Outbreak Management: Isolation Barrier precautions

•

www.cdc.gov/ncidod/dvrd/spb/mnpages/vhfmanual.htm http://www.who.int/csr/resources/publications/clinical-management-patients/en/

http://www.cdc.gov/ncidod/dvrd/spb/mnpages/vhfmanual.htm



























http://www.who.int/csr/resources/publications/clinical-management-patients/en/



























































Overview of VHFs

• Identify a minimum level of Standard Precautions – Establish routine hand washing – Establish safe handling and disposal of used sharps

• Minimize the use of sharps if possible

– Be prepared to intensify Standard Precautions and include VHF isolation precautions

– Identify a VHF coordinator to oversee and coordinate activities associated with VHF isolation precautions

WHO VHF Africa Manual

Overview of VHFs • Isolation Procedures

– Isolate the patient in a pre-selected area – Wear protective clothing:

• Scrub suit, gown, apron, two pairs of gloves, mask, headcover, eyewear, rubber boots

– Clean/disinfect spills, waste, and reusable safety equipment, soiled linens, and laundry safely

– Use safe disposal methods for non-reusable supplies and waste – Counsel staff about the risk of transmission – Limit exposure to patient (use an “authorized” list and use a guard) – Provide information to families and the community about VHF

prevention and care of patients – Consider all samples highly infectious – Surgical mask for patient for any patient movement


Overview of VHFs • Isolation Area

– Single room with adjoining toilet or latrine • Prefer to use chemical toilets if possible (5% sodium hypochlorite) • Changing area to put on PPE • Hand washing stations

– Separate building or ward for VHF patients only • An area in a larger ward that is separate and far away from other

patients • An uncrowded corner of a large room or hall • Any area that can be separated from the rest of the health facility


Overview of VHFs

– Disinfection solutions • 0.5% sodium hypochlorite (Dakin’s solution) • 2% glutaraldehyde • Phenolic disinfectants (0.5%-3.0%) • Soaps and detergents


Overview of VHFs

Identify a single lab personnel that will handle the samples -lab testing may not be available at all sites

Overview of VHFs • First Aid for Exposures

– Anticipate in advance – be prepared – Wash / irrigate wound or site immediately

– Mucous membrane (eye, mouth, nose)

• Continuous irrigation with rapidly flowing water or sterile saline for > 15 minutes

– Percutaneous

• Scrub for at least 15 minutes while copiously soaking the wound with soap or detergent solution

– Fresh Dakin's solution (0.5% hypochlorite)

Overview of VHFs • Casual contacts:

– Remote contact (same airplane/hotel) – No surveillance indicated

• Close contacts: – Housemates, nursing personnel, shaking hands, hugging, handling lab

specimens – Place under surveillance when diagnosis confirmed – Record temperatures twice daily x 3 wks – Notify for temperature >=100.40F

• High-risk: – Mucous membrane contact (kissing, sex) or needle stick or other penetrating

injury involving blood/body fluid – Place under surveillance as soon as diagnosis is considered – Immediately isolate for temperature >= 100.40F

If you are dealing with something where ribavirin may be of benefit

consider it as a post-exposure prophylaxis option

MMWR 1988;37:1-16

Additional Resources

Overview of VHFs • Summary for the Deploying Provider

– Identify the potential KNOWN risks in your AO – Identify your unit’s VHF coordinator – Keep track of all patient contacts – Identify your evac plan BEFORE you need it – Identify nearest medical support that can handle such patients

• Could your patient benefit from ribavirin? Other meds? • Have your nearest infectious disease and prev med support

on speed dial

– If going in support of the Ebola outbreak, familiarize yourself with the WHO handbooks and OTSG Clinical Practice Guidelines (in draft form)

Summary • VHF will start as flu-like illness and progress to organ failure

(bleeding may not be evident)

• Have high concern for the nosocomial risk as the treating provider

• Masks, gloves, gowns, and eye protection at a minimum

• Have isolation plan, post-exposure plan, and evac plans ready

• Ribavirin may be of benefit to some (not all VHFs, NOT EBOLA) if given early

Summary • Ribavirin is an investigational drug for VHF, thus you need to use

it on a research protocol • Avoid rodents

• If you are in a remote tropical locale with little epidemiologic data, and there are cases of something that appears hemorrhagic in nature, consider the unknown

• Experimental drugs and vaccines for selected VHFs are working

their way into human clinical trials

Final Thoughts • Any fever in a traveler to a malaria endemic region is

malaria until proven otherwise

• Any traveler with fever AND bleeding out of their eyeballs is VHF until proven otherwise

Crimean-Congo Hemorrhagic Fever


• Geographic regions – 12th Century: Tajikistan

• HF syndrome: blood in urine, rectum, gums, vomit

– 1944-45: First clinical description • Soviets (N=200, CFR = 10%) assisting peasants in Crimea

– 1956: febrile patient in Belgian Congo

– Common antigenic structure: Crimea & Congo viruses = CCHF

Extensive likely geographic distribution CCHF

= "'

- - =

1

2 2

"..".'


• Exposure Risks – Ticks (Hyalomma sp.) – primary vector

• Bite (increased exposure in Spring and Summer) • Crushed against skin

– Animals

• Rabbits, small mammals and birds – reservoir • Hoofed mammals (ungulates) – may be infected but won’t show evidence

of illness • Contact with dead animals (farmers, slaugherhouse, undercooked meat)

– Nosocomial risk (many HCP have died)

• Mortality Rates: 3-70% (typically 20-30%)

Crimean Congo Hemorrhagic Fever


• Diagnosis – ELISA (antigen capture as well as antibody) – RT-PCR (blood or tissue) – Virus isolation – Immunohistochemical staining

• Some predictors for severity in literature


• Containment & Prevention – Several reports in the literature indicating high risk of nosocomial

transmission to HCPs • One report of a patient acquiring CCHF from being in same hospital

room

– Turkish study of HCPs in setting with high number of cases showed high rates of PPE use was associated with only a 0.53% seroprevalence rate

• The 2 HCP who seroconverted in our initial case admitted to accidental mask slippage during care where aerosolization was a high risk

Int J Infect Dis. 2013 Nov;17(11):e1046-50 IntJ Infect Dis. 2009; 13: e105-7


• Containment & Prevention – Ribavirin

• High risk contacts can be considered • Use oral ribavirin

– For the CCHF case from Afghanistan, it was recommended that high risk contacts take 600 mg PO twice daily for 14 days

– Providers only took meds for 7 days in all cases, due to gastrointestinal side effects


• Treatment – Supportive Care – Ribavirin-CCHF controversy

• In-vitro activity against CCHF • No randomized controlled trials • Many case reports and case series indicating efficacy • Several others indicate no significant benefit • CDC does not “fully” recommend it’s use for CCHF • WHO recommends its use for CCHF (as well as Lassa, Junin,

and hantavirus with renal syndrome) • DoD has a phase 2 open label study for ribavirin treatment of

Lassa and CCHF (clinicaltrials.gov - NCT00992693)

CID 2013; 57:1270-4

• Severity Scoring Index – 0-2 = mild disease – 3-9 = moderate – 10-13 = severe

• Those with moderate disease had significantly better outcomes when receiving ribavirin

• Individuals with severe

disease did better with corticosteroids added



• Treatment – Ribavirin appears to be beneficial to overall survival in at least

moderate to severe disease

– Earlier the therapy the better (within first 4 days of illness)

– Corticosteroids in severe illness in addition to ribavirin may be beneficial to survival


• Vaccine Development – DNA vaccine study in mice not impressive

– Attenuated vaccinia (poxvirus) virus vector vaccine

• Expresses the CCHF virus glycoproteins • Protected all mice in challenge model

Vaccine. 2006 May 22;24(21):4657-66. PLoS One. 2014 Mar 12;9(3):e91516.

Lassa • Geographic regions

– Arenavirus first described in Nigeria in 1969 with distribution primarily in West Africa

– Outbreaks have occurred in: • Central African Republic • Guinea • Liberia • Nigeria • Sierra Leone (1987)

– 10-16% of all adult medical admissions 30% of adult deaths

– 25% of all maternal deaths

– Serological evidence found in Democratic Republic of the Congo, Mali, and Senegal

"Lassa fever virus [LFV] is endemic in Nigeria, and multi-mammate mice (_Mastomys_ spp.) are the rodent hosts. Lassa fever is now a serious problem in 23 of the 36 states of that country.“ -Nigeria Centre for Disease Control (NCDC), Federal Ministry of Health Weekly Epidemiology Report Vol. 5, No. 7 2015

Lassa • Exposure Risks

– Reservoir: Mastomys rodents • Rodent-to-human:

– Inhalation of aerosolized virus from rodent urine and feces – Ingestion of food or materials contaminated by infected excreta – Catching and preparing Mastomys as a food source

– Human-to-human: • Direct contact with blood, tissues, secretions or excretions • Needle stick or cut • Inhalation of aerosolized virus suspected

– Mortality Rates: 15-20% of hospitalized

Lassa • Exposure Risks

– Nosocomial Outbreaks • Dry season (JAN to APR) • All age groups and both sexes

– Pregnant women and fetus at high risk

• 80% fetal death

– The Kenema Government Hospital • January to April 2004 • 95 pediatric cases admitted • 50% of all cases aged under 15 years

– CFR was 30–50% in children <5 – CFR was 71% in children <1

Dr. Conteh attempted femoral venipuncture

and sustained a needlestick.

(WHO, Weekly Epi Record, MAR 2005)

Lassa • Diagnosis

– Clinical diagnosis is tough • May present with nonspecific symptoms

– Sore throat, swollen face and neck

• Hemorrhagic manifestations may not be evident • Neurologic symptoms (hearing loss, tremors, encephalitis)

– ELISA (antibody or antigen) – Viral culture (wouldn’t do this unless you have BSL-4) – Immunohistochemical staining of tissue – RT-PCR

Lassa • Containment & Prevention

– Rodent control (food storage is key) – Use of VHF barrier precautions can limit or eliminate

healthcare worker risks – Isolation of patients as discussed – Excreted in the urine for 3 – 9 weeks – Lassa vaccine

• USAMRIID had a vaccine based on a live viral platform that protected monkeys against a lethal challenge of Lassa

• Monkeys did not have symptoms, BUT were found to have circulating virus

PLoS Med 2005; 2(6): e183

Lassa • Containment & Prevention

– Ribavirin • High risk contacts can be considered

– Needle sticks or sharp injury – Mucous membrane or broken skin with blood/secretions – Participation in emergency procedures without PPE – Prolonged contact in enclosed space (e.g. med evac)

• Use oral ribavirin

– 800 mg daily for 10 days (EID article) – 35 mg/kg x 1 (up to 2.5 g) then 15 mg/kg (up to 1 g) TID x 10 d

CID 2010; 15;51(12):1435-41 EID 2010; 16 (20): 2009-2011

Lassa • Treatment

– Supportive Care – Ribavirin

• If used early (within 6 days) may significantly reduce mortality (76% to 9%)

– If you wait to start ribavirin after 6 days, rate goes up to 47%

• WHO recommends use (CDC also promotes its use) • DoD use via the open label study (see CCHF info above)

N Engl J Med 1986; 314:20–6. Antiviral Res. 1994;23:23 Rev Infect Dis. 1989;11:S750

Hantaviruses

Hantaviruses • History

– 1934: First published case of HFRS – 1951-1953

• United Nation’s troops in Korean War (near Hantaan River) • 3000 cases of fever + hemorrhage in 33%

– 1978: virus isolated – 1986: US – Korean military joint field exercise

• 14 cases of HFRS among 3,754 US Marines • 10 were hospitalized & 2 died (CFR = 14%) • Cases confirmed by serologic testing

MMWR Feb 19, 1988/37(6);87-90,95-6

Hantaviruses

• Geographic regions – “Old World”:

• Hantaan (Korea, China, Eastern Russia) • Dobrava (Balkans) • Seoul (Asia) • Puumala (Scandinavia, Western Russia, Europe)

– “New World”: Sin Nombre (U.S.), Andes

Field’s Virology, 4th Ed. Chapter 48

Hantavi rus Pulmonary Synd rome (HPS) Cases, by State of Exposure MN (2)

(7)

KS (16)

HPS Cases per State 1 - 15 16 - 50

50

Zern Cases

Total Cases; (N =624 in 34 Sca tes)

28 CMs Wirh an Unknown State of Expou re. Cum1lative Case Count

Source:Virat Special Pilthogens Branch, CDC Per StateValid as of July 9, 2011.

MT (35)

NO (10)

WY (14)

SD (15)

NE

Hantaviruses

• Exposure risks – Rodent excreta (aerosolized) – Reservoir

• Apodemus agrarius : striped field mouse (Hantaan) • Aedes flavicollis : yellow necked mouse (Dobrava) • Clethrionomys glareolus : bank voles (Puumala) • Rattus norvegicus : rat (Seoul)

– Demographic • Farmers, forest workers, soldiers in the field • Opening and utilizing previously unused buildings • 20 to 50 years in age • Male > Female

– Human to Human (very rare, with Andes virus)

Hantaviruses • Diagnosis

– Presentation: • Hemorrhagic Fever with Renal Syndrome (Old World)

– Incubation period may be 2-4 weeks – Flu-like symptoms, flushing or rash, red eyes, hemorrhagic

symptoms possible – Acute renal failure

» Puumala may have a milder presentation

• Hantavirus Pulmonary Syndrome (New World) – Early = nonspecific, flu-like symptoms – Late = severe shortness of breath and cough secondary to

pulmonary edema

– Lab diagnosis similar to other VHFs mentioned

Hantaviruses

• Containment & Prevention – Rodent control and maintain adequate food storage

– No need for VHF isolation procedures

– Vaccines are being developed

• Recently completed a phase 1 study at WRAIR – Phase 2a study started in July 2014

Hantaviruses • Treatment

– Supportive care – Dialysis frequently required for “Old World” – Ribavirin appears to be of benefit in “Old World” cases, by

decreasing mortality and improving renal morbidity • A double-blind, RCT of ribavirin in New World HPS did not

indicate effectiveness

JID 1991;164(6):1119-27 Antiviral Res. 2009 Jan;81(1):68-76

CID 2004; 39 (9): 1307-1313.

Emerging Threats

“There are known knowns; there are things we know that we know.

There are known unknowns; that is to say, there are things that we now know we don't know.

But there are also unknown unknowns – there are things we do not know we don't know.”

DONALD RUMSFELD

United States Secretary of Defense February 12, 2002

Be on alert for emerging infections…

• Lujo hemorrhagic fever (Zambia, South Africa) – 4 out of 5 patients died – The lone survivor received ribavirin

• Alkhurma hemorrhagic fever (Saudi Arabi, Egypt)

– Case fatality rate ~30% – Considered to be tick born – Hemorrhagic fever +/- encephalitis (similar to Kyasanur Forest Disease)

• Novel bunyaviruses (likely tick borne) – Severe Fever with Thrombocytopenia Syndrome virus (China) – Heartland virus (10 cases, 2 deaths; in Missouri, Oklahoma, and Tennessee)

• Lone star tick may transmit this virus

EID 2009; 15(10): 1598-1602

Emerging Threats

• Chapare Virus – Small cluster of cases occurred

Bolivia (2003-2004) – Hemorrhagic fever symptoms – Novel arenavirus found in 1 pt

• 22 yo male, died on DOI 14

in rural

PLoS Pathog 2008; 4(4): 1-6

United States Army Medical Research Institute of Infectious Diseases (USAMRIID)

Questions?

viral hemorrhagic fevers - walter reed army … · viral hemorrhagic fevers. ... – media –...

Documents